def print_letter_array(rows):
    for i in range(rows):
        start_char = chr(ord('A') + (i % 26))
        row = ''.join(chr((ord(start_char) - ord('A') + j) % 26 + ord('A')) for j in range(rows))
        print(row)

rows = int(input())

print_letter_array(rows)